Advances have been made in the research on color-tunable organic ultralong room-temperature phosphorescence (OURTP) materials. Due to the high cost of raw materials, complex and strict synthesis conditions, and low yields, it is hard to obtain cheap commercial OURTP materials within a short time. Therefore, it is of practical significance to research and develop new OURTP functions based on commercialized organic materials. In this study, the OURTP characteristics of melamine (MEL), a kind of commercially available, cheap, and pure organic material, were investigated and explored. MEL was found with color-tunable and excellent OURTP, the average lifetime can reach 0.74 s, and the phosphorescence quantum yield can reach 17%. Since the ratio of molecular phosphorescence of MEL to the ultralong phosphorescence mediated by H-aggregation differs with the excitation wavelength and their luminescence life spans are also different, the color of OURTP materials is dependent on both excitation wavelength and time. Moreover, the OURTP characteristics of MEL can be utilized in anticounterfeiting and information identification.

The relationship between the thickness of surface molecularly imprinted polymers (MIPs) and specific recognition performance of transferrin (Trf) as well as the quantitative relation between the grafting amount of Mn-ZnS room-temperature phosphorescence (RTP) quantum dots (QDs) (short for PQDs) and RTP signals for recognition of Trf was analyzed in this study. Based on analysis results, RTP protein mesoporous imprinting microspheres (SiO 2 −PQDs−MIPs) with high specificity and strong interference resistance were developed using a mesoporous SiO 2 nanomaterial that can create more three-dimensional precise recognition sites as the matrix and using PQDs with strong resistance to background fluorescence interference as the luminescent materials. A discriminatory analysis of Trf was realized by the phosphorescence quenching principle based on light quenching caused by the photoinduced electron transfer. The concentration range, limit of detection, relative standard deviation, and imprinting factor of Trf detection under pH 7.4 are 0.05−1.0 μM, 0.014 μM, 3.23%, and 3.09, respectively. Although the sensing signals of SiO 2 −PQDs−MIPs for proteins are based on the phosphorescence of PQDs, they are particularly suitable for specific recognition and accurate quantitative detection of proteins in biological fluids. Research conclusions are expected to realize high-efficiency recognition of target proteins in actual biological samples.

The direction synthesis of biofunctional nanomaterials with DNA as the template is of high application value. By using phosphorothioate–thymine single-stranded DNA (PS–T–ssDNA) as the template and through synthetic conditions optimization, novel low-toxicity and environment-friendly ssDNA-functionalized room-temperature phosphorescent quantum dots (PS–T–ssDNA RTP QDs) were prepared at low temperature (37 °C). Then, the quantitative RTP-based mercury­(II) (Hg2+) detection was achieved by utilizing the specific identifying ability of T-base-pair Hg2+ (T–Hg2+–T) and its photoinduced electron transfer. This RTP sensor in Hg2+ detection had a linear range of 0.02 to 0.8 μM and a detection limit of 4.8 nM. The dependence on RTP of QDs effectively avoids interference from background fluorescence and scattering light in the environment or biological samples. This sensor also possessed an RTP stability and a long service life and did not require sample pretreatment. Thus this sensor is suitable for environmental and quantitative Hg2+ detection in biological samples.

The URTP CNDs largely extends the collision time between T1 state exciton and O2, which improve quantum yield of singlet oxygen (1O2) in solutions, facilitating the photodynamic antibacterial and anticancer effects.

Fabricating PDAD–Mn–ZnS QDs nanohybrids as a facile room-temperature phosphorescent biosensor for detection of hyaluronic acid.